APPENDIX acid and alkyl iodide. The primary amine is decomposed with HNO.,, forming the alcohol, and nitrogen is evolved, CJlr.NIlo I UNO., - GUI../'.)!!: -I- No -[- II.O. The secondary amine forms the nitrosamine, insoluble in water (Coiy,NII | UNO.,- (C.II-^N.NO -1-II.p. I JiethyliutrnsrumiiL'. The tertiary amine is unacted on by nitrous acid, but, unlike the other two, unites with an alkyl iodide and forms the quaternary ammonium iodide (I lofmann), (<UIr,):,N I- CH:1I --- (Coirs):,NCIT,,T.> TrK'thyliuethyhunmomum iodide. The behaviour of nitrous acid with the aromatic amines is somewhat different (See Preps. 60, p. 157, and 62, p. 161). The primary amines may also be distinguished from second- ary and tertiary amines by the isocyanide reaction (p. 150), which consists in heating the amine with a Itttle chloroform and alco- holic potash solution. An intolerable odour of isocyanide is emitted, Coilr.NHo 1- CIICL. -I- 3KOIT ™ C«MflNC + 3KC1 + 3lU). PREPARATION 15. Ill3 Ethyl Acetate. —Esters may be obtained by the direct action of the alcohol on the acid as in the case of methyl oxalate. (Prep 26, p. roi). A certain quantity of ethyl acetate is also obtained from ethyl alcohol and acetic acid, '-but the action, which is a reversible one, stops when a certain proportion of the con- stitucnts have (-ombined (p. 234). It is represented thus : c,n,()ir i c:n:,.(:oon^;cii3.coocviB + n,o, /, which signifies that the ester and water react and regenerate f^ alcohol and acid, whilst the reverse process is in operation. P>y removing the water as it is formed by means of sulphuric acid or by distillation, this condition of equilibrium is disturbed and the reaction is completed. This does not, however, explain the fact, first discovered by Scheele and afterwards investigated by Fischer and Speier (see Prep. 99, p. 209), that a very limited f\ quantity of cone, sulphuric or hydrochloric acid will produce fe '